The present invention relates to a steam ejection nozzle for beverages.
Coffee-making machines of the professional type, i.e. for public concerns, for preparing hot beverages or for heating beverages in general, such as milk, water, chocolate and the like, use a nozzle for ejecting pressurized steam which produces, especially in milk-based beverages, a surface foam which distinguishes public-concern products from those which can be obtained with coffee-making machines for household use.
Actually, the real problem observed in coffee-making machines for household use with respect to professional ones is most of all related to the amount of steam which can be used to perform emulsification which produces the foam, which is greatly appreciated by consumers.
In fact, while professional coffee-making machines allow steam jets of considerable intensity, in coffee-making machines for household use the steam jet is limited by the capacity of the boiler built into the machine, i.e. by the amount of water which can be heated by the coffee-making machine for household use.
Furthermore, the skill of the operator is always necessary in order to obtain a considerable amount of foam.
In order to try to solve this problem, steam dispensing units have already been provided which are structured so as to facilitate the foaming of milk even with reduced amounts of steam.
A first known solution provides for a nozzle around the steam delivery duct which has a chamber connected to the outside by means of a hole which draws in air which is mixed with the liquid, so as to increase the amount of foam. Furthermore, in order to achieve a better foaming of the beverage, it is possible to provide a second hole, defined adjacent to the delivery duct, which allows to draw the beverage into said chamber, thus producing a forced and vortical circulation of the beverage both inside and outside the chamber delimited around the delivery channel.
Although this solution functionally solves the described problem, it generally has problems in providing a correct and complete cleaning of the delivery nozzle.
Another solution provides a turbine which is driven by steam and is arranged at the surface of the beverage so as to provide a vortical motion of the liquid which constitutes said beverage, thus emulsifying and foaming it.
This solution is structurally complicated and does not allow easy cleaning.